Since the 11 September 2001 attacks on America, the US government's "war on drugs" has been rather overshadowed by its "war on terror".

Now the White House is using one of the internet's fastest growing websites to spread its anti-drugs message.

The site, YouTube, allows people to put video material on the web that can then be watched by anyone with access to a computer and some simple software.

The site shows more than 100 million videos a day.

It is particularly popular amongst teenagers and there is an anti-establishment feel to many of the videos posted on it.

When, for example, you type in the key word "marijuana", hundreds of clips come up advocating its use.

The government's anti-drugs messages are now competing for attention alongside them.

The theme of many of them is how teenagers can avoid caving in to peer pressure.

Sharp and witty

One shows a guard dog at a lumber yard chasing a teenage boy. A voiceover from the boy tells us that his friends persuaded him to smoke a joint and then try to outrun the dog.

"I'm am idiot. I'm doing stupid things, and that ain't me," he says.

Another shows a group of teenage boys lounging on a couch after having smoked marijuana. One of their friends abstains, and tells the audience all the things that he could be doing whilst his friends lounge around in a drug-induced haze.

The videos are sharp and witty and they have all previously been aired on television stations in America.

"This has already been worth it because we are making people feel more connected to the government and this has not cost us a cent, it has been a good policy," says Raphael Lemaitre from the White House Drugs Office.

"We want people to take this issue seriously and get the right facts about illegal drug use."

Over the last 20 years government figures show a 30% reduction in the number of people regularly using illegal drugs - that is more than 7m fewer users.

But teenage drug use has not fallen as rapidly.

In the computer room at a youth club in Silver Springs near Washington, there is a degree of scepticism about the government campaign on YouTube.

"When people see that these videos are from the government they'll probably just back-click out of them," 14-year-old Axel Kabundji tells me.

"People will say: 'What's the government ever done for me? Forget it'."

'Counter-productive'

Fifteen-year-old Gabriel Sanchez was slightly more positive. "Maybe someone might stumble across one of these messages and get something out of it," he tells me.

It is hardly a ringing endorsement and that comes as no surprise to Michael Cornfield, professor of political management at George Washington University.

"All the research suggests that the more anti-drugs ads you show teenagers, the more likely they are to actually take them. When the government says something is bad, it's seen as cool," he says.

Mr Cornfield, who has studied how the internet is used for influencing social trends for more than a decade, believes that there could be a more effective anti-drugs strategy.

"The government should start recruiting young people to use MySpace, the social networking website," he says.

"To spread the anti-drugs message, peer pressure is always more effective than suggestions from the government."